Algal turfs have long been known to be efficient scrubbers of carbon dioxide, nutrients, and a variety of pollutants. Algal turfs are also known to produce biomass and oxygen, raise pH, and fix nitrogen. The productivity associated with tropical reefs can be at least partially attributed to the natural presence of algal turf performing one or more of these functions. In practical applications, algal turf scrubbing can be used for a variety of purposes including, but not limited to, filtering aquaria, nutrient and contaminant removal, and in the production of biomass as a fertilizer or food-based energy source.
The science of phycoremediation involves the use of algae to sequester or degrade water borne pollutants. U.S. Pat. No. 4,333,263 (hereinafter “the '263 patent”) to Walter H. Adey describes an “Algal Turf Scrubber” and is incorporated herein in its entirety by this reference. The '263 patent describes a method of producing an algal turf for use as a scrubber of carbon dioxide, nutrients and pollutants as well as biomass production. A growing surface, such as a screen, is provided on a water surface and used to grow spores or benthic microalgae. The growing surface is subjected to periodic water surge action to promote metabolite cellular-ambient water exchange and light is provided to promote growth. The '263 patent further describes that the growing turf is harvested before being overgrown by larger macroalgae.
No standardized substrate for algal growth has been developed for industrial phycoremediation application. More generally, products used to culture algae generally provide simple screens that, at least in certain respects, are inefficient and/or ineffective with respect to facilitating and optimizing algal growth. Alternatives to such screens and other traditional substrates that better facilitate improved algae use for bioremediation and fuel production purposes are desired.